Search Results (17,341)

Accurate lightning data are critical for disaster warning and climate research. This study systematically compares the Fengyun-4A Lightning Mapping Imager (FY-4A LMI) satellite and the Advanced Time-of-arrival and Direction (ADTD) lightning location network in the Beijing-Tianjin-Hebei (BTH) region (April–August, 2020–2023) using coefficient of variation (CV) analysis, Welch’s independent samples t-test, Pearson correlation analysis, and inverse distance weighting (IDW) interpolation. Key results: (1) A significant systematic discrepancy exists between the two datasets, with an annual mean ratio of 0.0636 (t = −5.1758, p < 0.01); FY-4A LMI shows higher observational stability (CV = 5.46%), while ADTD excels in capturing intense lightning events (CV = 28.01%). (2) Both datasets exhibit a consistent unimodal monthly pattern peaking in July (moderately strong positive correlation, r = 0.7354, p < 0.01) but differ distinctly in diurnal distribution. (3) High-density lightning areas of both datasets concentrate south of the Yanshan Mountains and east of the Taihang Mountains, shaped by topography and water vapor transport. This study reveals the three-factor (climatic background, topographic forcing, technical characteristics) coupled regulatory mechanism of data discrepancies and highlights the complementarity of the two datasets, providing a solid scientific basis for satellite-ground data fusion and regional lightning disaster defense. Full article

Background and Objectives: Access to anterior cruciate ligament reconstruction (ACLR) varies substantially across health systems, yet national-level data from Eastern Europe remain limited. This study provides the first nationwide, regionally stratified assessment of ACLR activity in Romania, examining geographic variation, socioeconomic and workforce determinants, and inequality. Materials and Methods: We conducted a retrospective cross-sectional analysis of all ACLRs reported in the national administrative hospital database (2017–2023), supplemented with demographic, GDP, and workforce statistics. Outomes included incidence per 100,000 population, private-sector share, and sex distribution. Regional differences were tested using Kruskal–Wallis and Dunn post hoc comparisons. Predictors of ACLR incidence and private-sector utilization were identified through multivariable Poisson and logistic models. Inequality metrics (Gini coefficients, P90/P10 ratios) and sensitivity analyses excluding Bucharest–Ilfov were also performed. Results: A total of 11, 080 ACLRs were recorded. Incidence varied markedly across regions, from a median of 40.0 per 100,000 in Bucharest–Ilfov to <1–3 per 100,000 in the South, South-East, and South-West (p < 0.001). Higher GDP per capita correlated with incidence (ρ = 0.36) and explained 45% of its variance. Private-sector involvement ranged from <5% in Bucharest–Ilfov and the South to 80–100% in the Centre, North-West, and South-East. In adjusted Poisson models, GDP, surgeon availability, and private-sector share were strong independent predictors of incidence (all p < 0.001). Private-sector access was primarily determined by the proportion of private orthopedic surgeons (OR 21.03). National inequality was extreme (Gini 0.842–0.752; P90/P10 > 10⁹), reflecting the concentration of procedures within a small number of counties. Results were consistent across sensitivity analyses. Conclusions: ACLR in Romania displays severe territorial inequities driven by socioeconomic development, workforce distribution, and uneven private-sector capacity. Targeted regional investment and coordinated workforce strategies are necessary to improve equitable access to surgical care. Full article

With accelerating urbanization, rivers have been severely polluted, resulting in widespread black and odorous waterways. The coagulation–sedimentation and contact oxidation bypass treatment process is characterized by low operational cost and simple operation and management. In this study, a coagulation–sedimentation–contact oxidation biofilter process was developed to treat heavily polluted malodorous blackwater. Among the tested biofilm carriers, rigid aramid fiber exhibited the fastest biofilm formation and the best pollutant removal performance. Based on a comprehensive evaluation of effluent quality and treatment capacity, the optimal operating conditions of the proposed process were identified as a PAC dosage of 50 mg/L, an air-to-water ratio of 7:1, and a hydraulic retention time (HRT) of 2 h. Under these conditions, the effluent concentrations of chemical oxygen demand (COD), ammonia nitrogen (NH₄⁺-N), and suspended solids (SSs) were consistently maintained below 30, 5, and 5 mg/L, respectively. Moreover, the optimized system demonstrated strong resistance to shock loading, maintaining stable operation at influent COD and SS concentrations of approximately 150 mg/L and 40 mg/L, respectively, while complying with the Class A Discharge Standard of Pollutants for Municipal Wastewater Treatment Plants. This study provides an efficient treatment strategy for malodorous blackwater remediation. Full article

Ischemic stroke is a major cause of long-term disability and death, with oxidative stress contributing substantially to post-ischemic injury. Reperfusion restores oxygen supply but simultaneously increases reactive oxygen species (ROS), amplifying secondary neuronal damage. This study examined time-dependent changes in systemic thiol redox status following transient middle cerebral artery occlusion (tMCAO) in rats. Plasma concentrations of cysteine (CySH), cystine (CySS), glutathione (GSH), and glutathione disulfide (GSSG), along with corresponding CySS/CySH and GSSG/GSH ratios and redox potentials (Eh), were evaluated 24 and 48 h after occlusion. At 24 h, thiol concentrations and redox ratios showed no significant differences between sham and tMCAO groups. By 48 h, a marked oxidative shift emerged, characterized by reduced CySH, elevated GSSG, and significant increases in both CySS/CySH and GSSG/GSH ratios. Redox potentials also demonstrated substantial oxidation at this time point. These findings indicate that prolonged ischemia–reperfusion induces systemic oxidative stress, with plasma redox status serving as a sensitive indicator of reperfusion-related injury. The results underscore the plasma redox status as a potentially sensitive biomarker of reperfusion-induced oxidative injury and support the therapeutic value of targeting redox imbalance to mitigate oxidative damage following stroke. Full article

Root anatomy serves as a critical indicator for understanding wetland plant adaptation strategies to environmental changes. Since water depth determines root oxygen demand while nitrogen addition regulates nutrient acquisition, the two factors exert significant and interactive effects on root anatomical structure. In this study, we established a controlled experiment employing three water depth treatments (W1: −10 cm; W2: 10 cm; W3: 30 cm), two nitrogen (N) forms (ammonium-N, nitrate-N), and four N addition levels (N0: 0 mg/L; N1: 40 mg/L; N2: 80 mg/L; N3: 160 mg/L). This design enabled us to analyze the effects of water–nitrogen interactions on the anatomical structure of reed roots to reveal wetland plants’ adaptive strategies to water-nitrogen fluctuations. The results indicate that (1) under nitrogen-free treatment, compared to the control group, the W1 treatment reduced the root aerenchyma proportion and the stele-to-root diameter ratio by 15.8% and 37.0%, respectively. In contrast, exodermis thickness increased by 32.4%, while epidermis thickness decreased by 33.7%. Under the W3 treatment, the aerenchyma proportion increased by 21.0%, the stele-to-root diameter ratio decreased by 22.2%, and exodermis thickness increased by 35.3%. (2) Compared to the nitrogen-free treatment, nitrate addition increased the root aerenchyma proportion under W1, W2, and W3 by 18.8%, 6.9%, and 18.3%. The stele-to-root diameter ratio increased by 27.9% and 12.7% under W1 and W2, but decreased by 10.8% under W3. Exodermis thickness increased by 26.3% under W2, whereas it decreased by 10.8% under W3. Epidermis thickness increased by 36.1% and 22.2% under W1 and W3, while a decrease of 12.7% occurred under W2. (3) Compared to the nitrogen-free treatment, ammonium addition increased the root aerenchyma proportion under W1, W2, and W3 by 13.6%, 13.2%, and 10.0%. The stele-to-root diameter ratio increased by 28.1% under W1 but decreased by 10.4% under W3. Conversely, exodermis thickness decreased by 20.2% under W1 while increasing by 12.6% under W3. Epidermis thickness increased by 26.3% and 20.8% under the W1 and W3 treatments. In summary, the root anatomical structure of P. australis adaptively responds to variations in water depth, nitrogen forms, and nitrogen concentrations by modulating aerenchyma proportion, the stele-to-root diameter ratio, exodermis thickness, and epidermis thickness. Future research should strengthen the study of the relationship between root anatomical traits and plant functions, to more comprehensively explore the adaptation mechanisms of wetland plants to global environmental change. Full article

Tea plants (Camellia sinensis) uniquely hyperaccumulate fluoride (F) and concurrently exhibit a preference for ammonium nitrogen (NH₄⁺-N) over nitrate nitrogen (NO₃⁻-N). However, the mechanistic basis for co-existence of NH₄⁺-N preference and F hyperaccumulation in C. sinensis remains unexplored. Here, we investigated F accumulation and translocation with varying N supplies (0 mM and 2.854 mM N with NH₄⁺-N:NO₃⁻-N ratios of 3:1, 4:0 and 0:4) and F concentrations (0, 8 and 16 mg·L⁻¹ NaF) to reveal the mechanism driving NH₄⁺-N preference and F hyperaccumulation in C. sinensis. Results show that NH₄⁺-N supply enhanced H⁺ efflux, mobilizing aluminum (Al) to form mobile Al-F complexes for translocation to shoots, thereby alleviating F toxicity in roots. This process was facilitated by transporters including CsCLCd, CsCLCe, CsCLCf2 and CsFEX. In contrast, NO₃⁻-N promoted root sequestration of F as immobile calcium (Ca)-F complexes, exacerbating damage. Under NO₃⁻-N supply, CsCLCb primarily mediated NO₃⁻ transport, while CsCLCc, CsCLCe, CsCLCf1, CsCLCf2 and CsFEX were involved in F transport. In leaves, CsCLCd, CsCLCe, CsCLCf1, CsCLCf2, CsCLCg and CsFEX mediated vacuolar sequestration under both N conditions. These findings elucidate that NH₄⁺-N preference is mechanistically linked to F hyperaccumulation through an Al-assisted translocation pathway, which confers tolerance by exporting F from roots. Full article

Objective: Alzheimer’s disease (AD) and other forms of dementia are a heterogeneous group of neurodegenerative diseases characterized by progressive cognitive decline. Differential diagnosis between AD and other dementias is crucial for choosing the optimal treatment strategy. Currently, cerebrospinal fluid (CSF) analysis remains the most accurate diagnostic method, but its invasiveness limits its use. In this regard, the search for reliable biomarkers in the blood is an urgent task. Methods: The study included 31 dementia patients (23 women and 8 men) diagnosed via interdisciplinary consultations and neuropsychological testing (MMSE ≤ 24). CSF and blood plasma samples were collected and analyzed using Luminex technology. Biomarker concentrations were measured, and statistical analyses (ANOVA, Kruskal–Wallis, and Pearson correlation) were performed to compare groups and assess correlations. Results: Levels of Aβ40 and Aβ42 in CSF were significantly lower in patients with AD compared with non-AD dementia (p = 0.02 and p < 0.001, respectively). The Aβ42/40 ratio in CSF was higher in patients with non-AD dementia (p = 0.048). The concentration of Aβ42 in blood plasma was increased in patients with AD (p = 0.001). Positive correlations were found between Aβ42 in CSF and TDP-43 in plasma in non-AD dementia (r = 0.97, p < 0.001), as well as between neurogranin and TDP-43 in plasma in AD (r = 0.845, p < 0.001). Conclusions: The study demonstrates the potential of blood biomarkers, in particular Aβ42, for the differential diagnosis of AD and other forms of dementia. The discovered correlations between CSF and plasma biomarkers deepen the understanding of neurodegenerative processes and contribute to the development of noninvasive diagnostic methods. Full article

Fermented forest litter (FFL) is a biofertilizer obtained by anaerobic fermentation of forest litter combined with agricultural by-products. Its production involves an initial one-month solid-state fermentation of oak litter mixed with whey, molasses and wheat bran, followed by a one-week submerged fermentation-called the “activation” phase-during which the solid FFL is fermented with sugarcane molasses diluted in water. This study aimed to evaluate the effects storage duration (6, 18 and 30 months), and temperature (ambient and 29 °C) on the activation phase. For this purpose, pH, sugar consumption and metabolite production dynamics were monitored. Under all experimental conditions, the pH dropped to values close to 3.5, sucrose was rapidly hydrolyzed, and glucose was preferentially consumed over fructose. Fructose was metabolized only after glucose was depleted, suggesting the involvement of fructophilic microorganisms. The time-course evolution of lactic acid (LA) concentration was adequately fitted by the Gompertz model (R² > 0.970). The highest LA_max concentration (6.30 g/L) and production rate (2.16 g/L·d) were obtained with FFL stored for 6 months. Acetic acid (AA) and ethanol were also detected reaching maxima values of 1.19 g/L and 0.96 g/L, respectively. Their profiles varied depending on the experimental conditions. Notably, the AA/LA ratio increased with the age of the FFL. Overall, sugar consumption and metabolite production were significantly slower at ambient temperature, than at 29 °C. These results contribute to a better understanding of the metabolic dynamics during FFL activation and highlight key parameters that should be considered to optimize future biofertilizer production processes. Full article

Utilizing forestry and agricultural byproducts like wood and hemp residues advance sustainable additive manufacturing (AM), while reducing material costs. This study investigated the development and characterization of wood–sodium silicate composites incorporating hemp hurd and hemp fibers for AM applications. Formulations varied by wood fiber type (unsifted, 40 mesh, and pellet), sodium silicate concentration (50–60 wt%), and hemp hurd content (0–15 wt%). Properties evaluated include particle size and bulk density of the constituent materials, rheological behavior, extrusion performance, composite bulk density, and flexural and compressive strengths. Rheology and extrusion were largely influenced by the liquid content. Mixtures with low liquid content (50 wt% sodium silicate) had high motor power and low viscosity. As liquid content increased, motor power decreased, while viscosity increased up to 55 wt% and then decreased at 60 wt%. Mechanical properties correlated with particle size, where finer particles enhanced strength. A cost analysis was conducted using raw material prices to determine the economic feasibility of each formulation. Finally, the formulations were evaluated based on strength-to-cost ratios, extrudability and processability. The formulation with pellet wood fibers, 55 wt% sodium silicate, and 10 wt% hemp hurd achieved a high ratio of 73.0 MPa/$ while maintaining low motor power. This formulation offered additional benefits which are discussed qualitatively. Full article

Common methods for detecting Drosophila suzukii (spotted-wing drosophila, SWD) in fruit, such as microscopy, physical extraction, and incubation, are time-consuming and may underrepresent egg and first instar larvae counts, the smallest life stages of SWD. To address these limitations, we evaluated a quantitative real-time PCR (qPCR) protocol to detect and quantify SWD eggs using a linear model of the log-transformed ratio of eggs to sample volume (µL) in Tris buffer and fruit tissue. Compared to traditional approaches, this method reduces identification time from several weeks to approximately five hours. We observed a negative linear correlation between qPCR cycle threshold and egg concentration in both standard and fruit tissue samples, with similar model fits (R² = 0.7215 for field fruit tissue; R² = 0.874 for standard samples). This DNA-based protocol improves infestation detection speed and accuracy by enabling rapid, species-specific identification of D. suzukii in fruit tissue, addressing limitations of morphological identification of eggs and larvae. Further refinement for fruit tissue could enhance real-world applicability. Rapid detection may enable timely assessment of varietal resistance to SWD and support safer control strategies targeting early life stages, helping to prevent pest development and fruit degradation. Full article

In this work, kaolin/chitin (K/Ch) composite aerogels with different mass ratios were successfully fabricated via a freeze–drying approach. The influence of kaolin content on the microstructure, properties and hemostatic performance of the composite aerogels was systematically investigated. The results demonstrated that the incorporation of kaolin endowed the chitin-based aerogels with tunable porous structures, excellent water absorption capacity (up to 4282% for K_0.25/Ch₂), and enhanced water retention (73.7% for K₂/Ch₂ at 60 min). Moreover, the K/Ch composite aerogels exhibited good biodegradability, no cytotoxicity (cell viability > 91.9%), and no hemolysis (hemolysis rate < 1.5% at all test concentrations). In vitro hemostatic evaluations revealed that the composite aerogels exhibited rapid blood coagulation (blood clotting time of 16 s for K₂/Ch₂) with a blood coagulation index (BCI) as low as 0.5%, which was attributed to the synergistic effect of the physical adsorption of chitin and the coagulation cascade activation by kaolin. These findings indicated that the K/Ch composite aerogels could be used as novel natural hemostatic materials for potential effective and rapid hemostasis. Full article

To address the challenge of optimizing hydrological parameters for nitrogen pollution control in paddy polders, this study coupled the Stella eco-dynamics model with an external optimization algorithm and developed a nonlinear programming framework using the water surface ratio and inflow rate as decision variables and the maximum nitrogen removal rate as the objective function. The simulation and optimization conducted for the Hongze Lake polder area indicated that the model exhibited strong robustness, as verified through Monte Carlo uncertainty analysis, with coefficients of variation (CV) of nitrogen outlet concentrations all below 3%. Under the optimal regulation scheme, the maximum nitrogen removal rates (${\eta }_1$, ${\eta }_2$, and ${\eta }_4$) during the soaking, tillering, and grain-filling periods reached 98.86%, 98.74%, and 96.26%, respectively. The corresponding optimal inflow rates ($Q^{*}$) were aligned with the lower threshold limits of each growth period (1.20, 0.80, and 0.50 m³/s). The optimal channel water surface ratios ($A_1^{*}$) were 3.81%, 3.51%, and 3.34%, respectively, while the optimal pond water surface ratios ($A_2^{*}$) were 19.94%, 16.30%, and 17.54%, respectively. Owing to the agronomic conflict between “water retention without drainage” and concentrated fertilization during the heading period, the maximum nitrogen removal rate (${\eta }_3$) during this stage was only 37.34%. The optimal channel water surface ratio ($A_1^{*}$) was 2.37%, the pond water surface ratio ($A_2^{*}$) was 19.04%, and the outlet total nitrogen load increased to 8.39 mg/L. Morphological analysis demonstrated that nitrate nitrogen and organic nitrogen dominated the outlet water body. The “simulation–optimization” coupled framework established in this study can provides quantifiable decision-making tools and methodological support for the precise control and sustainable management of agricultural non-point source pollution in the floodplain area. Full article

With the increasing requirements for “Green Mine” construction, Cemented Tailings Backfill (CTB) has emerged as the preferred strategy for solid waste management and ground pressure control in underground metal mines. However, full tailings, characterized by wide particle size distribution and high fine-grained content, exhibit complex physicochemical properties that lead to significant non-linear behavior in slurry rheology and strength evolution, posing challenges for accurate prediction using traditional empirical formulas. Addressing the issues of significant strength fluctuations and difficulties in mix proportion optimization in a specific lead–zinc mine, this study systematically conducted physicochemical characterizations, slurry sedimentation and transport performance evaluations, and mechanical strength tests. Through multi-factor coupling experiments, the synergistic effects of cement type, cement-to-tailings (c/t) ratio, slurry concentration, and curing age on backfill performance were elucidated. Quantitative results indicate that solids mass concentration is the critical factor determining transportability. Concentrations exceeding 68% effectively mitigate segregation and stratification during the filling process while maintaining optimal fluidity. Regarding mechanical properties, the c/t ratio and concentration show a significant positive correlation with Uniaxial Compressive Strength (UCS). For instance, with a 74% concentration and 1:4 c/t ratio, the 3-day strength increased by 1.4 times compared to the 68% concentration, with this increment expanding to 2.0 times by 28 days. Furthermore, a comparative analysis of four cement types revealed that 42.5# cement offers superior techno-economic indicators in terms of reducing binder consumption and enhancing early-age strength. This research not only establishes an optimized mix proportion scheme tailored to the operational requirements of the lead–zinc mine but also provides a quantitative scientific basis and theoretical framework for the material design and safe production of CTB systems incorporating high fine-grained full tailings. Full article

In extreme scenarios, to prevent the leakage of jamming coordination information, the jammers must proactively terminate their communication functions and implement jamming resource scheduling via Non-Networked Cooperation. However, current research on this non-networked jamming approach is relatively limited. Furthermore, existing algorithms either rely on networked interactions or lack cognitive strategies for the surrounding communication countermeasure situation. For example, they fail to adapt to dynamic changes in electromagnetic noise and struggle to determine jamming effectiveness, leading to low jamming efficiency and severe energy waste in non-networked scenarios. To address this issue, this paper establishes a game process and corresponding algorithm for non-networked communication countermeasures and designs cognitive, cooperative, and scheduling strategies for individual jammers. Meanwhile, a novel performance metric called the “Overall Communication Suppression Ratio (OCSR)” is proposed. This metric quantifies the relationship between “sustained full-suppression duration” and “ operating duration of the jamming system,” overcoming the defect that traditional metrics cannot evaluate the dynamic jamming effectiveness in non-networked scenarios. Experimental results indicate that although the OCSR of the proposed Intelligent Concentric Circle Algorithm (ICCA) is significantly lower than that of the Full-Power Jamming Algorithm (FPJA), ICCA extends the operating duration of the jamming system by 4.8%. This achieves non-uniform power setting of jammers, enabling flexible and dynamic jamming in non-networked scenarios and retaining more battery capacity for jammers after overall jamming failure. Full article

This study produces high-purity nano-silica from corn straw ash (biomass power plants) using an alkaline fusion-derived sodium silicate solution. CO₂ replaces traditional acids in the carbonation reaction, enabling high extraction yield (93.11%). The process addresses the gap in directly utilizing combustion ash for such high-purity silica. Key optimal conditions identified were 5 M aq. HCl concentration, NaOH fusion reagent, 1:1.2 mixing ratio, 3 M aq. NaOH solvent, and 12 h ripening. The resulting nano-silica achieved 92.73% purity, 10–50 nm particle size, 270 × 10⁻⁵ m³/kg dibutyl phthalate (DBP) absorption, 55.9916 m²/g specific surface area, 6.38% loss on drying (LOD), and 6.69% loss on ignition (LOI). These properties meet national standards for premium, loosely structured nano-silica. This method provides an economical and effective silicon source, reducing costs and offering economic-environmental benefits. Full article